html {
    box-sizing: border-box;
    font-size: 10px;
}

*, *::before, *::after {
    box-sizing: inherit;
}

body {
    padding: 0;
    margin: 0;
    background-color: #3BC1AC;

    /* 顺序：右下，左下，中间，右上，左上 */
    background-image:
    radial-gradient(circle at 100% 150%, #3BC1AC 24%, #42D2BB 25%, #42D2BB 28%, #3BC1AC 29%, #3BC1AC 36%, #42D2BB 36%, #42D2BB 40%, transparent 40%, transparent),
    radial-gradient(circle at 0    150%, #3BC1AC 24%, #42D2BB 25%, #42D2BB 28%, #3BC1AC 29%, #3BC1AC 36%, #42D2BB 36%, #42D2BB 40%, transparent 40%, transparent),
    radial-gradient(circle at 50%  100%, #42D2BB 10%, #3BC1AC 11%, #3BC1AC 23%, #42D2BB 24%, #42D2BB 30%, #3BC1AC 31%, #3BC1AC 43%, #42D2BB 44%, #42D2BB 50%, #3BC1AC 51%, #3BC1AC 63%, #42D2BB 64%, #42D2BB 71%, transparent 71%, transparent),
    radial-gradient(circle at 100% 50%, #42D2BB 5%, #3BC1AC 6%, #3BC1AC 15%, #42D2BB 16%, #42D2BB 20%, #3BC1AC 21%, #3BC1AC 30%, #42D2BB 31%, #42D2BB 35%, #3BC1AC 36%, #3BC1AC 45%, #42D2BB 46%, #42D2BB 49%, transparent 50%, transparent),
    radial-gradient(circle at 0    50%, #42D2BB 5%, #3BC1AC 6%, #3BC1AC 15%, #42D2BB 16%, #42D2BB 20%, #3BC1AC 21%, #3BC1AC 30%, #42D2BB 31%, #42D2BB 35%, #3BC1AC 36%, #3BC1AC 45%, #42D2BB 46%, #42D2BB 49%, transparent 50%, transparent);
    background-size: 100px 50px;

    font-family: sans-serif;

    display: flex;
    min-height: 100vh;
    align-items: center;
}

.voiceinator {
    width: 50rem; /* 1rem === 12px */
    padding: 2rem;
    margin: 0 auto;
    background-color: white;
    border-radius: 1rem;
    box-shadow: 0 0 5px 5px rgba(0, 0, 0, 0.1);

    position: relative;
    z-index: 1;

    overflow: hidden;
}

h1 {
    width: calc(100% + 4rem);
    margin: -2rem 0 2rem -2rem; /* 往左上角移动 */
    padding: 0.5rem;
    background-color: #ffc600;
    border-bottom: 5px solid #F3C010;

    font-size: 5rem;
    font-weight: 100;
    font-family: 'Pacifico', cursive;
    text-align: center; /* 文字居中 */
    text-shadow: 3px 3px 0 #F3C010;
}

.voiceinator select,
.voiceinator input,
.voiceinator textarea,
.voiceinator button {
    width: 100%; /* 每一项均占父宽 */
    padding: 10px; /* 隔开文字与边框 */
    margin: 10px 0; /* 隔开每一项 */
    border-width: 0; /* 去掉 select，textarea，button 默认的边框 */
    background-color: #353535; /* 去掉边框后，加上背景色代替边框起区分作用 */

    display: block;

    font-size: 2rem;
    color: white;
    outline: 0;
}

textarea {
    height: 20rem;
}

.voiceinator button {
    width: 49%;
    /*border-width: 0;*/
    margin-bottom: 0;
    background-color: #ffc600;
    border-bottom: 5px solid #F3C010;

    float: left; /* 由垂直排列改为水平排列 */

    font-family: 'Pacifico', cursive;
    /*font-size: 2rem;*/

    cursor: pointer;

    position: relative;
}

.voiceinator button:active {
    top: 2px; /* 按钮被点击时，通过增加 top 值，会产生按钮往下移动的效果 */
}

.voiceinator button:nth-of-type(1) {
    margin-right: 2%; /* 两个按钮间加一点间距，隔开两个按钮 */
}
